Increase_brightness (and decrease)

Configuration
1

Hi all,
I’m unable to find the definition of the increase_brightness action (and decrease_brightness) made available to my dimmers (published via zigbee2mqtt).

I haven’t set it up, it’s not an automation or a service (that I can find) or a script and I have no idea of whether the step change in brightness can be modified. I’m not sure I am looking for a solution, but more to understand the underpinning of this action.

I have inspected the messages that come through via mqtt but wasn’t able to find a correlation. Can anybody help explain this please? Is it an internal action assigned to light type dimmer devices by default?

Thanks - Pedro.

2

it is part of service turn on:

  - service: light.turn_on
    entity_id: light.light_kitchen
    data:
      brightness: 50
3

Thanks! I understand how .increase_brightness uses .turn_on, but do you know where this is defined?